


The Things that Define Us

by Nonbinaryweirdo



Category: Haikyuu!!
Genre: Alternate Universe - Soulmates, Angst, Emotional Hurt/Comfort, Eventual Fluff, Gen, Hinata Shouyou is a Good Friend, M/M, Romantic Soulmates, Slow Burn, Soulmate-Identifying Marks
Language: English
Status: In-Progress
Published: 2021-03-18
Updated: 2021-03-18
Packaged: 2021-03-26 22:08:05
Rating: Not Rated
Warnings: Creator Chose Not To Use Archive Warnings, No Archive Warnings Apply
Chapters: 2
Words: 2,494
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/30112749
Author URL: https://archiveofourown.org/users/Nonbinaryweirdo/pseuds/Nonbinaryweirdo
Summary: When Yamaguchi Tadashi thought about who his soulmate was, he always secretly hoped it would be his best friend. He never really cared who his soulmate was, or if he didn’t have one, but there was a nagging voice in the back of his head that always wished it was Tsukishima.Whenever Tsukishima Kei thought of soulmates it made his head spin. He didn’t think that the universe should decide who you should spend your life with, that should be your choice and your choice only.Neither of them had any idea of what was to come.
Relationships: Hinata Shouyou & Yamaguchi Tadashi, Tsukishima Kei & Yachi Hitoka, Tsukishima Kei & Yamaguchi Tadashi, Tsukishima Kei/Yamaguchi Tadashi
Comments: 3
Kudos: 6





	1. Hey Siri, are Soulmates Real?

**Author's Note:**

  * For [sakura_mochi](https://archiveofourown.org/users/sakura_mochi/gifts).



> Not me starting another story when I already have like three other WIPs- (-_-;)
> 
> Anyway- this is my first gifted work, I really hope you like, sakura_mochi!
> 
> I just started this and already I've researched a lot for this fic. I'm having a fun time writing it and I hope you have a fun time reading it!

It was a normal school day, excluding the fact that it was his birthday when Tsukishima got his soulmate tattoo. He had kinda been hoping he wouldn’t get one at all. Some people just didn’t get them, and he was perfectly happy to be one of them. But the universe had other plans. 

When he woke up on his 18th birthday he felt strange. When he got up to brush his teeth and looked in the mirror he felt even stranger. His mark wasn’t big, it was a small strawberry just above his collar bone, on the right side, almost in the place his neck and shoulder met, but it made his stomach drop. From fear or excitement, he didn’t know. When he got dressed he made sure to put on a hoodie that would cover up his mark, even though it was uncharacteristically warm for that time of year. 

His whole ride to school he was agitated. He kept thinking about who his soulmate could be. Soulmates were usually the people closest to you, the universe pulling you close despite the mark’s absence. He wasn’t exactly close to anyone, _except Yamaguchi _, but Tsukishima pushed that thought down. When he got to school he locked his bike up and when inside to find his best friend.__

___**__** ____ _

____Yamaguchi was sitting in the classroom at his desk, waiting for Tsukishima. When Tsukishima entered the room his face lit up and the shorter boy shot up from his chair._ _ _ _

____“Hi, Tsukki!” He waved excitedly and Tsukishima gave him a small, almost unnoticeable, smile as he sat down. “Did you get your mark?” Yamaguchi asked, having calmed down enough to be semi-serious. Tsukishima tensed and nodded slightly. “Oh! Cool! Where?”_ _ _ _

____“I’m not showing you,” he snapped defensively. The dark-haired boy frowned and twisted his face in slight disappointment. He quickly turned back to excitement, though._ _ _ _

____“I wonder what mine will be!”_ _ _ _

____“Do you want a soulmate?” Tsukishima asked, fishing his headphones from his bag._ _ _ _

____“Of course! It’ll be nice to have someone to tell everything, with no hesitation. I like the idea of someone being made just so that we could, like, complete isn’t the right word, but… make each other better, I guess!”_ _ _ _

____“You just sounded like Hinata, don’t do that again,” he teased, a small smirk on his lips. Yamaguchi blushed then settled down as their teacher entered the classroom and sat at her desk._ _ _ _

____“I’m just excited,” he mumbled._ _ _ _

____“Hm?” Tsukishima questioned. He didn’t hear what his friend had said, because he had placed his headphones on his ears._ _ _ _

____“Nothing,” Yamaguchi said._ _ _ _

____“Okay…” The blond boy put his headphones back on his ears as Yamaguchi set his head in his arms._ _ _ _

_____**__** ____ _ _ _

______Tsukishima rode back home on his bike, after volleyball practice, he was excited to eat his cake, do his homework, and go to bed. He had a worksheet to do over the weekend, but it wasn’t a lot. He planned to hang out in his room and read for most of the weekend if Yamaguchi didn’t want to do anything with him. The thought of his best friend brought his mind back to soulmates as he rode into his driveway. He punched in the garage code and parked his bike inside, thinking about all the things they had learned about soulmates in, what, like fourth grade? He barely remembered his childhood, let alone the week they learned about soulmates in /fourth grade/._ _ _ _ _ _

______He closed the garage door and opened the door into the house, slipping in quietly. His parents weren’t home, like always, they never got home until later, but he didn’t mind. He went to the kitchen and pulled out the slice of strawberry shortcake he had bought the day earlier, suddenly remembering his mark again he reached up to touch the place on his skin where it sat, taunting him. He grumbled at the cake, his mark, and himself, as he walked upstairs to his bedroom._ _ _ _ _ _

______His room was warm and welcoming, more so than the rest of his house. Today he noticed the touches that Yamaguchi had given his room were starting to get more pronounced. Photos hanging on the wall of the two of them. One of Yamaguchi’s jackets hanging on the hooks among Tsukishima’s own. The worksheets he had in a folder on his desk for helping his best friend study. All of them marks the smaller boy had left on his life. Thinking about it made his heart ache and swell at the same time._ _ _ _ _ _

______Sitting down at his desk, he put down the piece of cake and shucked off his backpack. He set his backpack on the floor next to the desk and started to eat his cake. Cake and other baked goods had never been his thing, that was until Yamaguchi started to get into baking, and Tsukishima was pulled along to go shopping, and fed sample cakes and cookies. His favorite cake that his friend had made was strawberry shortcake. Yamaguchi’s was always soft and the perfect amount of sweet. The cake he had now was nowhere near as good, but it was still strawberry shortcake. After he finished he pulled out the two-page packet he had for homework and set off finishing it._ _ _ _ _ _

_______**__** ____ _ _ _ _ _

________The packet took two hours to complete, longer than it should have. But he was done, and tired so he put it away in his bag and went to lay on his bed. He knew he wouldn’t be sleepy, he never felt like going to sleep until 10:30, and it was only around 7:40. He sighed and got out his phone, scrolling through Instagram until he heard his parents come home. Sighing, he got up to greet them._ _ _ _ _ _ _ _

________Walking down the stairs he heard his parents flirting, _gross _, he thought. Both his mom and dad were hopping around the kitchen, making sandwiches. They were laughing as his dad put on some music and spun his mom around. Tsukishima stood in the doorway and huffed a quiet laugh at his parents. His mom noticed him and beckoned him over. Pushing off the doorway he had been leaning on he went over to kiss his mom’s cheek.___ _ _ _ _ _ _ _

__________“Did you get a mark, sweety?” She asked. She and Kei’s father were soulmates and they had an expectation for him to marry his soulmate too. Kei chuckled a little uncomfortably and pulled back his sweatshirt so they could see the little strawberry just above his collar bone. “Oh, sweety. That’s so cute,” his mom preened. She put a hand on his other shoulder to pull him down so she could see it better._ _ _ _ _ _ _ _ _ _

__________“Is that a strawberry?” His father asked. Kei nodded and pulled away from his mother’s grip and let go of the neck of his sweatshirt, letting his fall back into place and cover the mark._ _ _ _ _ _ _ _ _ _

__________“Well, whoever your soulmate is, I hope they’re a kind person,” his mom sighed. She handed him a plate with two sandwiches, he thanked her and went back to his room. He ate his sandwiches and watched youtube until he fell asleep._ _ _ _ _ _ _ _ _ _

___________**_44 days later_** ____ _ _ _ _ _ _ _ _ _

____________Yamaguchi woke up on his birthday and raced to his mirror to see where his mark was. The mirror in his room was smudged and dirty, but he didn’t care. When he got to the mirror he inspected his face and neck closely, and that’s when he saw it. On the outside of his left wrist, there was a small pair of square glasses. They looked almost the same as the ones that Tsukishima wore. He laughed in relief and excitement, bouncing around his room. He ran down the hall to wake his parents. His mom and dad were already awake and sitting in their bed, reading._ _ _ _ _ _ _ _ _ _ _ _

____________“Mom, Dad, I got my mark!” He exclaimed._ _ _ _ _ _ _ _ _ _ _ _

____________“Oh, honey. That’s wonderful! Come here my little strawberry,” his mom called him over. “Do you have any idea who it could be? Here, let me see it,” his mom asked as he sat down on the edge of her bed. He handed his left hand to her as he talked._ _ _ _ _ _ _ _ _ _ _ _

____________“I mean, it could be this one person, they have glasses like that. But, I’m not sure if they would like me back.”_ _ _ _ _ _ _ _ _ _ _ _

____________“Who wouldn’t like you back, muffin?” His mom teased, pinching his cheek as she released his wrist. “To me, your mark looks like your friend, Tsukishima’s glasses.” Tadashi pulled away a bit from his mom when she said that. “And if he is your soulmate, platonic or otherwise, we fully support you, my little strawberry. Right, honey?” She asked. Tadashi’s father, who was watching his son and wife talk nodded._ _ _ _ _ _ _ _ _ _ _ _

____________“We love you, no matter what.”_ _ _ _ _ _ _ _ _ _ _ _

____________“Thanks, I love you. I’m gonna go make breakfast, want anything?” Tadashi asked._ _ _ _ _ _ _ _ _ _ _ _

____________“Could you bring me some tea?”_ _ _ _ _ _ _ _ _ _ _ _

____________“Some tea for me as well, thank you.”_ _ _ _ _ _ _ _ _ _ _ _

____________“You got it!”_ _ _ _ _ _ _ _ _ _ _ _

____________As he walked down the stairs and got his breakfast and three cups of tea ready he thought about how having Tsukushima as a soulmate would be. He already knew he was a little in love with his best friend, but would Tsukishima like him back?_ _ _ _ _ _ _ _ _ _ _ _

**Notes for the Chapter:**

> The chapters get longer, don't worry. 
> 
> Tell me if I made any mistakes, constructive criticism is good and helps me become a better writer!


	2. Why Him?

**Notes for the Chapter:**

> Get ready for some angst, because it's all downhill from here!
> 
> I wrote most of this like 20 minutes ago on a sadness high because I started my period. <(¬＿¬<)

Yamaguchi was extremely excited to go to school the next day. He was hoping that Tsukishima was his soulmate, platonic or otherwise. Usually, when someone is your soulmate and you meet for the first time with both of your maks, the marks glow. If they glow but stay monochrome, that person is a platonic soulmate. If they glow and turn colorful that person is a romantic soulmate. The dark-haired boy just hoped his marks would glow at all. 

When he got to school Tsukishima was just locking up his bike. Yamaguchi ran over to him but stopped abruptly as he felt a faint tingling on his wrist. He looked down to where it was coming from and found his mark glowing. He looked up at Tsukishima and gasped as he saw his best friend’s mark glowing as well, although faint through his scarf, it was glowing. 

“I- um- need to go,” Tsukishima stuttered out. Yamaguchi barely had time to process what was happening before Tsukishima was gone. Yamaguchi looked down to his mark, it was colored orange and black now. A small sob ripped from his throat, he clamped a hand to his mouth, resisting the urge to fall to the ground.

**__**

The rest of the school day was hell. Tsukishima never realized how much he depended on Yamaguchi to make everyday life more enjoyable. He missed his best friend’s quiet teasing remarks, the way he would do anything to get a genuine smile from Tsukishima. But for the rest of the day, Yamaguchi was completely quiet. He didn’t even raise his hand when Tsukishima knew full well that the younger boy knew the answer to the question the teacher asked. 

Yamaguchi wasn’t acting like himself, and that hurt Tsukishima more than he could articulate. 

**__**

Volleyball practice had to be the worst, _by far _. The gym felt empty without Yamaguchi and his encouraging smiles and reassuring words. The team was messy without their captain, even if Hinata was an excellent vice-captain.__

__Tsukishima sighed as he sat on the bench a few feet away from where Hinata and Kageyama were sitting. Kageyama sent him a quick glance, clearly looking at his colored mark. Hinata hit his best friend on the head, and sent Tsukishima an apologetic look._ _

__“Kageyama wants to ask if you know where Yamaguchi is,” Hinata asked. There was no hostility in his voice, quite the opposite actually, but Tsukishima still felt like he’s just been punched in the gut at the words._ _

__“I don’t know why he isn’t here,” Tsukishima answered coldly, hopefully shutting down the conversation._ _

__“He was really quiet in class all day, and I didn’t see him at lunch, did you Kageyama?”_ _

__“Boke, Hinata we sat together for lunch. If you didn’t see him, neither did I,” Kageyama grumbled. Tsukishima made a small _tsk _noise and pushed himself off the bench.___ _

____He walked over to the basket of balls the first years were hanging around and grabbed one, disturbing their conversation. “Sorry,” he mumbled as they went back to talking. Technically, their break didn’t end for another 3 minutes, but Tsukishima couldn’t stand sitting on a bench and hearing those two idiots talk about Yamaguchi._ _ _ _

____He threw the ball into the air and kept it from hitting the ground until coach Ukai blew his whistle for the end of the break. Tsukishima tossed the ball back into the basket and shuffled over to the small group gathered around a whiteboard marked with a hypothetical match and different strategies for different plays. Tsukishima tuned out Ukai and Hinata’s words as he thought of Yamaguchi._ _ _ _

____He barely noticed when the group dispersed and they went back to the small drills as they always did when a captain was missing. He sighed and when to the net to block one of the first year’s spikes until practice was over and he could go home._ _ _ _

____**__**_ _ _ _

____Yamaguchi barely made it through the day. He kept his head down and didn’t talk. Making it to practice in his condition was not an option, so he called his mom and asked her to pick him up. His mother obliged and picked him up right after school, on her way home from work. When she asked what was wrong, and why he wasn’t going to practice, the small string that was keeping him above the pit of despair he was so afraid to fall into snapped, and he fell._ _ _ _

____A choked sob left his throat before he even realized he was crying, tears splattering into his cupped palms. His mom pulled into a parking lot, unbuckled her seatbelt, and hugged him across the center console. She patted his back as he sobbed into her shoulder.____

___“Do you want to talk about it, my love?”_ _ _

___“I-I guess I should,” his mom just nodded encouragingly. “Y-you were right. About Tsukki being my soulmate, I mean. B-but when they glowed,” he showed his mom the orange and black pair of glasses on his left wrist. “He ran away and didn’t talk to me all day. Does he hate me now? He must be disgusted by us being soulmates. We’re best friends, _of course _, he hates the thought of romance between us-”___ _ _

___“Honey, you’re overthinking this. He was probably overwhelmed as well. He just needs some time to process too,” she placed a gentle hand on his cheek and rubbed soft circles under his eye. He smiled sadly and let his head be held by her sturdy hand. “Now, let’s stop and get some ice cream before we head home, okay? And then we can talk more over a sad movie,” Tadashi nodded and slumped back into his seat. Maybe the sadness can be kept at bay for a little bit by his mother’s kind words and soft touches. _Maybe _.___ _ _


End file.
